1. Field of the Invention
The present invention relates to a method and apparatus for erection of a form for pouring a concrete wall.
2. Brief Description of the Prior Art
A common prior art method of providing a form for pouring a concrete wall utilizes as the main components: (a) rectangular forming panels with spaced through holes, (b) tie rods which fit through the panel holes and interconnect oppositely positioned panels, (c) wedging plates which hold the two ends of the tie rods securely to the panels, (d) waler brackets, which often serve the dual function of a wedging plate and a bracket for carrying a waler, (e) one or more walers which provide structural reinforcement and keep adjacent panels in proper alignment, and (f) other support structures to keep the assembled form erect.
Usually one wall of the form is erected by placing a plurality of panels in a vertically erect position, aligned with one another in a single plane which defines one surface of the concrete wall which is to be poured. Tie rods are inserted through the holes in each panel, and each tie rod is secured by one end to its related panel by means of a wedging plate or a wedging plate with a waler bracket thereon. As each individual panel is placed in its erect position, it is usually held there either by some sort of scaffolding structure, temporary framework or bracing struts. Walers, usually in the form of long 2 .times. 4 wooden pieces, are placed along the outer surface of the panels and are held securely in place by the waler brackets.
After one set of panels is assembled and properly braced to form the one wall of the form, the opposite wall of the form is then erected by placing a second set of panels opposite the first set so that the second set of panels fits over the second oppositely positioned ends of the tie rods. Then wedging plates are inserted over the protruding heads of the tie rods and pushed into wedging engagement to hold the second set of panels securely to the tie rods, thus, securing the two opposite sets of panels one to the other. Some of these wedging plates are in the form of waler brackets, and walers are likewise placed against the second set of panels to insure proper alignment and structural reinforcement.
When it is desired to form a wall of greater vertical dimension, requiring sets of panels one on top of another, the task becomes more complex in that more structural reinforcing is required, and usually scaffolding or the like, to hold the panels and other components in place and provide access to the upper sets of panels by the workmen. In such an operation, usually the first set of panels is erected in much the same manner as disclosed above, with horizontal walers holding the panels in alignment. Then a temporary scaffolding is erected, after which a second set of panels is placed on top of the first set in planar alignment therewith. Support for this second upper set of panels is usually provided by the scaffolding, and horizontal walers are then placed against the upper second set of panels. Then quite often a set of vertical walers or studs is placed against the horizontal walers to provide for proper alignment between the upper and lower sets of panels and also provide structural reinforcement. After this, a second two sets of panels are erected opposite the first two sets in somewhat the same manner as described above.
In a competitive industry such as the construction industry, as expected, there have been many attempts to make improvements in this system, and a number of patents have made various improvements in the configuration of the waler brackets themselves. For example, U.S. Pat. No. 2,977,659, Buxton, discloses a waler bracket which is pivotally attached to either a tie rod or a wedging plate. Other examples of modified forms of waler brackets are disclosed in the following U.S. Pat. Nos. 3,030,059, Jahn; 3,241,803, Foy; 3,286,976, Lynch; 3,047,264, Terry; 3,547,398, Furr; and 3,729,159, Foster.
In most of these prior art patents noted above, the waler bracket serves its conventional function of providing a bracket to carry the waler and it is usually placed in wedging engagement in some manner with the tie rod. The modifications are usually made to obtain such advantages as greater durability, better application of pressure against the associated panel, ease of installation and removal after the concrete pour has been completed, etc.
There have been other efforts to make various improvements in the tie rods and examples of these are disclosed in U.S. Pat. No. 3,785,610, Dagiel, and U.S. Pat. No. 3,075,272, Buyken.
U.S. Pat. No. 3,327,986, Oury, shows a more comprehensive system for erecting forms for concrete walls. Abutting panels are joined one to another by plates which extend between two panels with projecting studs or pins extending into the panels. Each plate is then secured by means of a "hairpin" which is placed in wedging engagement with the plate to cause it to be in firm engagement with the panels. To engage a waler or a "kicker bracer", U-shaped brackets are provided, and L-shaped brackets are adjustably and rotatably mounted on modified hairpin brackets either for walers or catwalks. While the system in the Oury patent may provide certain advantages in convenience of erection of the forms, it does require more sophisticated hardware than is normally used.
Even though there have been many specific hardware improvements in the apparatus required to erect forms for pouring concrete walls, one of the major expenses still remains the considerable labor involved not only in erecting and securing the forms themselves, but also in erecting bracing and scaffolding. A further labor cost is the installation of a substantial number of walers, and in the case of forms requiring upper and lower sets of panels, the placing of vertical studs or walers over the horizontal walers.
Accordingly, it is an object of the present invention to provide a system for erecting forms for pouring concrete walls, which system eliminates some of the labor involved in erecting such forms and utilizes hardware of a relatively simple and easily workable nature.